Can a private member be accessed by a function which is not a member function?
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In this articleIn some circumstances, it's useful for a class to grant member-level access to functions that aren't
members of the class, or to all members in a separate class. These free functions and classes are known as friends, marked by the Syntax
friend declarationsIf you declare a Functions declared in a Although
functions with global scope can be declared as
The preceding example enters the class name In C++11, there are two forms of friend declarations for a class:
The first form introduces a new class F if no existing class by that name was found in the innermost namespace. C++11: The second form doesn't introduce a new class; it can be used when the class has already been declared, and it must be used when declaring a template type parameter or a Use
An error occurs if you use
In the following example,
Use
Use
To declare two classes that are friends of one another, the entire second class must be specified as a friend of the first class. The reason for this restriction is that the compiler has enough information to declare individual friend functions only at the point where the second class is declared. Note Although the entire second class must be a friend to the first class, you can select which functions in the first class will be friends of the second class. friend functionsA
The following example shows a
Class members as friendsClass member functions can be declared as friends in other classes. Consider the following example:
In the preceding example, only the function A
In that case, all member functions in class
Friendship isn't mutual unless explicitly specified as such. In the above example, member functions of A managed type (in C++/CLI) can't have any
Friendship isn't inherited, meaning that classes derived from The following figure shows four class declarations: Implications of friend relationship Inline friend definitionsFriend functions can be defined (given a function body) inside class declarations. These functions are inline functions. Like member inline functions, they behave as though they were defined immediately after all class members have been seen, but before the class scope is closed (at the end of the class declaration). Friend functions that are defined inside class declarations are in the scope of the enclosing class. See alsoKeywords FeedbackSubmit and view feedback for Can private members be accessed by member functions?Private: The class members declared as private can be accessed only by the member functions inside the class. They are not allowed to be accessed directly by any object or function outside the class. Only the member functions or the friend functions are allowed to access the private data members of the class.
Can a nonNon-member functions of a class will not have access to the private data of another class.
Which function is a way to give private access to a nonWe can access private method in other class using the virtual function, A virtual function is a member function which is declared within a base class and is re-defined (Overridden) by a derived class.
Can you access a protected member of a class from a nonProtected members in a class are similar to private members as they cannot be accessed from outside the class. But they can be accessed by derived classes or child classes while private members cannot.
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